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By P. M. Sullivan

Galvanizers' sal skimmings have been treated by two methods of leaching in attempts to produce preflux solutions suitable for use in galvanizing operations. Both water-leaching and acid-leaching procedures are effective, except in severely exhausted skimmings when water-leaching becomes impractical. A preliminary analysis of the skimmings is not required. Solutions in the recommended concentration range can be produced conveniently by control of pH, specific gravity, and chlorine content. A technician would require only a short period of training to be able to perform the operations described.

Jan 1, 1958

The Wattle Dam gold mine, located near Kambalda in the Goldfi elds region of Western Australia has recently progressed to an underground operation and is now believed to be Australia's highest grade operating gold mine. At end of March 2010, the deposit had reserves of 132 000 t @ 20.8 g/t for 88 000 oz and by the end of June 2010 had produced 110 000 oz from open-pit and underground mining. The Wattle Dam main lode is characterised by very coarse gold mineralisation. Gold occurs as cm to decimetre fracture fi ll veinlets, shear surface coatings and erratic fl akey clusters. The gold has no quartz or silica association and lacks adjacent low-grade mineralisation or alteration assemblage. Geologically it appears atypical of Archaean lode gold deposits and may represent an extreme end member of the type. Definition of the lode is largely dependent on effective geological identification of the host lode zone and an understanding of the erratic distribution and grade behaviour of a high-nugget, coarse gold deposit. Dependence on assay data to defi ne the lode zone would result in the deposit being mined incorrectly and much of the deposit being left unexploited. This paper discusses the geology, coarse gold characteristics and defi nition methods which are used to successfully defi ne and mine the deposit.

Aug 1, 2010

By Gustav Jahner, Michael Baltrusch, Norbert Hoffmann

Near the port city of Whitby in the north-east of England, Anglo American (AA) is setting up the deepest mine in the UK, which will have a depth of 1,500m. The purpose of the project is to extract and transport polyhalite, both underground, and to market it globally. As part of the construction works, BAUER Technologies Ltd, the UK subsidiary of BAUER Spezialtiefbau GmbH, constructed three different shafts using the diaphragm wall technique, with depths of up to 120m. In order to ensure the specified vertical tolerance of maximum 200mm, several measurement methods were applied, and the results were documented in a 3D model. Complex de-sanding plant technology and specially developed polymer products were adopted to regenerate the trench supporting bentonite-slurry.

Sep 1, 2022

By John J. Simmons

There is considerable interest in the iron and steel industry in the development of technologies that can reduce carbon dioxide emissions, as the iron and steel industry is the third largest producer of carbon emissions in the world, after automobiles and the power generation industry. The E-Iron Iron Nugget Making Process, invented by Dr. Komar Kawatra and Dr. Tim Eisele, provided a major breakthrough in the iron making process as the process uses biomass in the form of hard wood or soft wood as the reductant in the place of coal. Dr. Kawatra recognized that biomass is rich in both carbon monoxide and hydrogen, two important reducing agents. This resulted in initial experiments conducted by Dr. Kawatra and Dr. Eisele in the laboratories of the Chemical Engineering Department of Michigan Technological University (Michigan Tech) that prepared self-reducing pellets with wheat flour as the reductant and limestone/dolomite as the flux. Initial results were encouraging so they extended their work to include hardwood, which is in huge supply in the forests of Michigan and Minnesota, as the reductant. Dr. Kawatra has also applied the E-Iron Technology to other iron bearing minerals to produce pig iron grade iron nuggets. He used the E-Iron Process to convert red mud, a high iron waste product of the aluminum industry, into pig iron nuggets with the rare earth elements reporting to the slag. This work resulted in a patent with Dr. Kawatra and Dr. Michael Archambeau named as the inventors. Dr. Kawatra then extracted the rare earth elements as a separate high value bi-product using oxalic acid, which he produced from carbon dioxide. Dr. Kawatra also conducted a test program that produced pig iron nuggets from New Zealand beach sands. The vanadium in the beach sands was retained in the iron nuggets, recoverable as a valuable bi- product in a separate process. The titanium dioxide in the beach sands reported to the slag. This demonstrates the potential use of the E-Iron Process to convert the large ilmenite reserves in Northern Minnesota into pig iron and titanium dioxide. Another use of the E-Iron Process discovered by Dr. Kawatra was its ability to produce iron nuggets from manganiferous ores. Dr. Kawatra was able to direct the manganese into either the metal or slag by adjusting process temperature. The above discoveries are included in several patents that were assigned to Carbontec Energy. This presentation will only address the use of the E-Iron Process to produce pig iron nuggets from steel mill waste and un-pelletized, mid-grade iron ore. Carbontec Energy Corporation agreed to sponsor additional research directed at improving this new technology that would later be trade named, The E-Iron Process. Carbontec Energy conducted further work that proved that the E-Iron technology could also convert steel mill waste into metallurgically acceptable iron nuggets. Carbontec also collaborated with the Lawrence Livermore National Laboratory and Purdue University Northwest to conduct a Department of Energy (DOE) sponsored program that would use their high performance computer capability to both verify and model the E-Iron Process. Purdue University Northwest reported that the E-Iron Process can produce pig iron nuggets with 85% less carbon emissions than a blast furnace. The E-Iron Process is similar to the ITmK3 process, developed by Kobe Steel, that also produces iron nuggets but uses coal as the reductant.

Feb 1, 2025

By H. T. Mulryan

Talc is used as an essential ingredient in a wide variety of plastics applications ranging from polyester body patch compounds through polypropylene automotive, appliance, and household furniture components to high performance parts made from liquid crystal engineering resins. The paper focuses on polyolefin applications; the three tier market for talc in polypropylene; the effects of various talcs in typical compounds; and trends in each market segment. Emphasis is given to emerging markets, examples of which are polypropylene compounds which mimic higher cost resins, and polyethylene films, customer requirements for talcs for these purposes are discussed.

Jan 1, 1993

By Guilherme Bougleux Michelin Assunção

O projeto visa o estudo da reatividade e da resistência do coque, combustível tradicionalmente utilizado na siderurgia, relacionando às diversas condições presentes no alto-forno. Para a realização da pesquisa, foram utilizadas amostras de coque de uma empresa siderúrgica nacional. O coque foi analisado através dos ensaios Coke Reactivity Index (CRI) e Coke Strength After Reaction (CSR) no Laboratório de Processos Metalúrgicos da Universidade Federal de Minas Gerais (UFMG). Os testes foram realizados em tempos e temperaturas pré-determinados para simular as diversas zonas percorridas durante a descida do termo-redutor nos altos-fornos. Os resultados mostraram a viabilidade termodinâmica da gaseificação do coque a partir de 900°C, sendo possível calcular a energia de ativação da reação de Boudouard a 1100°C, e a correlação entre CRI e CSR coque.

Aug 17, 2017

By David Hanson, Sean Warren, Chaparral Berry

"Coal bumps, also referred to as dynamic failure events or coal bursts (Lawson, Weakley, and Miller, 2016), continue to be a hazard in underground coal mines. While current design methods have significantly reduced the occurrence of coal bumps, they have not been completely eliminated. This paper investigates a correlation between coal compositional components, coal molecular structure, and probability of coal bumps in an effort to deepen understanding of coal behavior in an effort to reduce hazards in underground coal mines.Samples from the Penn State Office of Coal (PSOC) Department of Energy Coal Samples (DECS) were obtained for Fourier Transform Infrared Spectroscopy (FTIR) analysis using the KBr pellet method. Peaks indicative of the coal molecular structures were obtained using spectral integration software. These data, combined with published elemental data, were compared to historic bump occurrence in order to establish a possible correlation. Finally, results based on multivariate analysis of the elemental and FTIR data with bump status as the dependent variable suggest that elemental sulfur and molecular structure can be used as an indicator of bump susceptibility within the sample set considered.INTRODUCTIONThe study of coal requires consideration of multiple variables: percentages of organic and inorganic components, organic component origins, coal age, pore structure, cleat density, elemental composition, etc. Examining coal in situ increases the number of variables, such as coal depth, seam thickness, surrounding stratigraphy, and so forth. This collection of variables influences the subsequent behavior of coal simultaneously, and weighing their relative impact is a challenge for researchers. “A problem never exists in isolation; it is surrounded by other problems in space and time” (Ackoff, 1956). Having a substance such as coal that we know so much about, and yet so little, we have to ask what can be learned.An experimental study using Fourier Transform Infrared Spectroscopy (FTIR) was undertaken to determine if the chemical structure of coal contains information which may lead to a better understanding of triggers or attributes which may, in turn, lead to an increased probability of a dynamic failure event. While a full analysis of the factors driving dynamic failure are beyond the scope of this study, it is possible that a better understanding of the chemical structure of coal will lead to an increased knowledge of its inherent behavior, including its propensity to burst."

Jan 1, 2019

By A. B. Hooker

The flame safety lamp with metal-gauze enclosure was invented by Sir Humphrey Davy more than a century ago, primarily for its safe light; however, it soon became the standard device for detecting the presence of methane in mine atmospheres. It still is the most widely used device for this purpose and is also the most practicable means of detecting deficiency of oxygen in coal mines. A permissible flame safety lamp is similar in all respects to one that, after a series of tests, has been approved by the Bureau of Mines as safe for use in gassy mines. However, safety depends largely upon the way lamps are maintained and used.

Jan 1, 1944

By Frank E. Cash, Roy G. Stott

This circular describes four modern change houses of the Lake Superior iron - ore district , all conceived and constructed since 1937. The oldest change house described herein was constructed and occupied in 1938 , yet it embodies the modern improvement of air - conditioning . The purpose of this report is to describe and illustrate improvements with regard to health and safety features combined in the construction , arrangement , ventilation , heating ,lighting , and other features , with the aid of photographs , sketches , and diagrams . The modern change house is a fire - resistant structure in which intermingling of men in mine clothes and men in street clothes , hazardous dust , heat and humidity , crowding , poor lighting , slippery and muddy floors , and inadequate facilities for clothes and for bathing have been largely eliminated . The miner coming off shift at a modern mine no longer faces the elements when he gets off the cage . He travels through a tunnel to the change house , where he is cooled gradually by room temperatures as he passes from the mineclothes section and shower room to the street - clothes room . He is assured of dry clothes when he is ready for them . No longer is he sent out of the change house into a muddy yard to drive away as best he can . The modern change house has an improved parking lot and graveled or concreted walkways from it to the change house entrances .

Jan 1, 1949

By Andrew Middleton, Mark Wyatt

"The Brickworks Marketplace Project is a significant shopping centre development in inner north west Adelaide constructed by Badge Constructions in 2014 and 2015. The site was a former brickworks with a deep pit containing various extents of uncontrolled fill which was to remain on site, and with a remaining void up to 6 m in depth. The existing uncontrolled fill was improved using the High Energy Impact Compaction system, and the pit backfilled using a quarry crusher byproduct selected by trial and a recycled crushed concrete and bricks and compacted in deep lifts. This approach resulted in significant savings in compaction time, cost and building foundations. The settlements of various parts of the completed works have been monitored since February 2015 and this monitoring has demonstrated small settlements which meet the user’s constraints.INTRODUCTIONThe Torrensville Brickwork Markets project involved the transformation of a former brickworks and clay pit site into a regional 17,000m2 shopping centre, opening in June 2015.The site was a former brickworks with adjoining clay borrow pit. The clay pit had been partially backfilled over many years with ‘uncontrolled’ fill comprising ‘clean’ soil, bricks and kiln dust typically of the following thicknesses:??of the order of up to 7 m to 10 m but locally up to 15 m in the western part of the site??2 m to 5 m in the south-eastern part of the site; and??less than 0.5 m in the north-eastern part of the siteAnecdotal reports suggested compaction of some of the fill may have been undertaken, although this not able to be confirmed nor records obtained.Initially it was proposed to take up the existing uncontrolled fill, sort and recompact or remove to landfill, followed by backfilling in conventional means over 500,000 cubic metres of imported filling to a thickness of up to approximately 6m to backfill the former pit. This work represented a significant cost and was not economically viable.During early negotiations, the contractor proposed an alternative to retain and ground improve the existing filling on site, and to backfill the pit with fill placed and compacted in deep lifts, thereby significantly improving the economics, environmental and community impacts of the proposed works.The developer agreed to the proposal with the following performance criteria:??a settlement of =10 mm after 10 passes by the Impact Compactor (on existing subgrade areas);??a bearing capacity of 250 kPa for high level footings;??a maximum long term differential settlement of 40 mm (measured over 16 m), ie. 1 in 400; and??a minimum modulus of 40MPa."

Jan 1, 1900

By Jun Wang, Bo Zhang, Wenqing Qin, Guanzhou Qiu, Xiaozhen Ma, Key Lab of Biohydrometallurgy of Ministry of Education, Fen Jiao, Central South University, Yansheng Zhang

"Arsenic contained in minerals sulphides such as enargite and tennantite can represent not only a significant penalty element in base metals production, but also a disadvantage to the environment through producing the toxic emissions to the atmosphere. The achieving separation of arsenic bearing minerals either at an early stage in floatation or from the floatation concentration is significantly beneficial to the economic. However, there was no feasible commercial method of separation at the flotation stage because of its similar flotation properties with many other copper sulphides. In this work, the selective floatation of enargite from copper sulphide concentrate containing maily covllite, chalcoctie, bornite and enargite was investigated. A low arsenic concentrate with As 0.2%, Cu 22% and a high arsenic bulk concentrate with As 7.65%,Cu 33.65% were obtained. It was indicated that Ca(ClO)2 is the effective depressor and the optimum floatation condition was obtained. Most enargite could be floated at pH 11 and controlling the pulp potential at 290 mV SHE. Furthermore, the arsenic removal from the high arsenic bulk concentrate by hydrometallurgy methods was study. The results showed that the reaction temperature and the concentrations of NaOH were the most important variables affecting the rate of arsenic removal. A low arsenic concentrate with As 0.24%, Cu 37.80% was obtained in the optimum leaching condition.INTRODUCTIONArsenic is mainly produced as a by-product of base metals smelting, in particular copper concentrate. China has imposed an upper limit of 0.50% arsenic for concentrates entering (Long et al., 2012). Arsenic amount of copper concentrate within 0.40% has also been imposed in China, and above which will be introduced about 50 RMB penalties per ton for each 0.10% increasing by smelters now. Therefore, it is necessary to remove arsenic from the copper concentrate.In copper concentrate, arsenic is mainly in the form of arsenopyrite (FeAsS), enargite (Cu3AsS4) or tennantite (Cu12As4S13). There are two types of arsenic in the separation of copper and arsenic: arsenopyrite and arsenic bearing copper mineral. It is easier to separate arsenopyrite from the copper sulphide by flotation in comparsion with the separation of enargite or tennantite from non-arsenic copper minerals (Pineda et al., 2015). The main difficulty in the separation of arsenic copper mineral from non-arsenic copper sulphides is their extremely similar floatability, which depends on the fact that tennantite and enargite contain high copper content (Pineda et al., 2015)."

Jan 1, 2016

By Marcelo Gonçalves Pereira

Os roletes de planicidade estão instalados na posição frontal dos laminadores. O histórico do equipamento mostra um tempo entre falha de 6 meses, caracterizadas principalmente por fratura da gaiola e danos na pista dos rolamentos lado acionado. Danos no eixo na região de montagem aumentam em torno de 10 horas a indisponibilidade da máquina para recuperação do mesmo. A partir da RCFA realizada nos rolamentos falhos, identificou-se deficiência de lubrificação, sinais de ovalização, descascamento e desalinhamento na pista de rolagem, fratura da gaiola. Com base nos modos de falha foi realizado a alteração e adequação da lubrificação dos mancais, melhora do sistema de vedação e alteração da disposição de montagem dos rolamentos de contato angular de back-to-back (“O”) para face-toface (“X”). Com as modificações realizadas os roletes atualmente operaram por mais de 14 meses sem ocorrência de falha.

Aug 17, 2017

By F. A. Forward

Introduction The main line of ascent in the development of the nickel industry may be traced back through the International Nickel Company of Canada, Limited, to its earliest antecedents, the Canadian Copper Company and the Orford Copper Company. Mining geology is but one aspect of the overall development of this organization, and the stress it has placed on geology grew according to the need. In the early days, intensive geology was not required because ore supply was not one of the main problems of this or any of the pioneer companies. The difficulty then was to find economic methods for reducing the ores to nickel and copper, and markets for absorbing nickel in the face of a limited demand from consumers heavily prejudiced in favour of the New Caledonia product. "Very early in the history of the region it was patent to everyone that to share in the full benefits of the industry the same individuals or company must control the whole of the operation necessary to manufacture the finished product' (1, p. 45). These conditions were fulfilled for the International Nickel Company in 1902 when the Canadian Copper Company (incorporated 1886), with its ample ore supply, took the initiative to merge its interests with those of the Orford Copper (Refining) Company (incorporated 1887) to form the new company which, with reorganizational changes, emerged as the producer of the overwhelming bulk of the world's nickel. The Mond Nickel Company, Limited, entered the field in 1899 with a refining process, and over a period of years acquired ore through purchase of mining properties. This Company operated successfully and independently until 1929 when its assets were joined with those of the International Nickel Company in order to permit the most economic exploitation of the Frood-Stobie orebody in which both Companies were interested.

Jan 1, 1948

By S C. Dominy

Gravity amenable gold ores are those that after comminution produce liberated particles, composites and/or carriers that can be recovered by gravity separation means. Recovery depends upon mineralisation type and the comminution and concentration method used. Any in situ ore with more than 20 per cent of gold greater than 100 µm in size is likely to have a strong gravity recoverable component. A less traditional approach is where the gold is sulfide-locked and the gold carrier plus any liberated gold is recovered via continuous gravity recovery following fine crushing. Specific tests are undertaken to determine the level of gravity amenable gold within a deposit. The principal methodology is the gravity recoverable gold (GRG) test, which consists of three sequential liberation and recovery stages. For continuous gravity recovery (CGR), the sample is fed over a laboratory Wilfley table to simulate continuous recovery of the gold. Tails from the feed can be progressively re-ground and re-tabled to develop a grade-recovery curve. Primary geology and gold particle size-distribution have a strong effect on the mass of sample required to provide representative results for both tests. Where low-grade ore contains very coarse gold, substantially larger sample masses are required. Experience has shown that GRG and CGR values can vary throughout an orebody, particularly within different geological-grade domains. A testing regime must consider sample frequency and support.

Sep 5, 2011

By Seneviratne SP

The excessive displacement of the seam floor in headings (i.e. roadways) called 'floor-heave' is often experienced in the underground mines of the Southern Coalfield of New South Wales. Apart from interfering with the mining operations, the phenomenon could be detrimental to the stability of the pillars left for support leading to an unpredictable increase in the subsidence of the overlying strata. The latter could pose a serious problem, particularly in the design of partial extraction layouts of mining for areas where subsidence is to be controlled. The susceptibility of the floor of different rock materials and thicknesses in a given `panel and pillar' partial extraction geometry was examined by two- dimensional Finite Element Modelling of the displacements, stresses and failure zones around the excavations. The modelling, assuming elastic behaviour of the materials, indicated that the maximum vertical displacements of the floor increased substantially as the Young's Modulus of the material decreased to less than 7GPa and the thickness of the layer increased. The results also discount the possibility of a properly designed panel and pillar geometry in the Southern Coalfield of New South Wales being unable to adequately control surface subsidence through the pillar, or its core independently of the yielded ribs, penetrating the floor.

Jan 1, 1992

By H. Winkelmann

The author, who himself has worked inn the field with various types of torsion balances, expresses in the article his experience with the recently marketed Haff-Torsion-Balance. The advantages of practical work with Haff?s s torsion balance as compared with other types are mentioned. In spite of low weight and corresponding small dimensions (Model M = 23.5 kg., Model Al = 11.5 kg.) the sensitiveness is not less than that in the largest instruments. It is at 1.10-9, which is proved by calculations. A comparison with the corresponding values of other types of torsion balances (Eötvös, Askania, Gepege) is given. The mechanical features of the instrument are briefly described, and the balance is illustrated by a, cross section of it. -- W. Ayvazoglou. DETERMINATION OF THE ELEMENTS OF THE MAGNETIC AND GRAVITATIONAL FIELDS INDUCED BY AN INFINITELY LONG HOMOGENEOUS CYLINDER By G. A. Gamburzeff Gerlands Beiträge zur Geophysik, Band 19, Heft 2/3 Leipzig, 1928, pp. 210-230. The present work is a. contribution to the quastion of the reason for the magnetic and gravitational anomalies in the government of Kursk (Russia).

Jan 1, 1929

By F. E. Block, Robert R. Brown, A. W. Henderson

The chlorination of Cr₂ 03 (chromic oxide ) in the presence of carbon with CC14 (carbon tetrachloride ) and COCl2 (phosgene ) chlorinating agents was investigated by employing the radioactive tracer carbon By tagging carbon mixed with Cr₂ 0з , the chlorination reaction was evaluated in terms of the competitive reaction of the elemental carbon and the carbon contained by the chlorinating agent . A unique gas - analysis train was used to separate the chlorination product gases ; CO , CO₂ , and COC12 . The C¹ activity of the gases was determined and used to calculate the reactivity of each source of carbon . Reactivities were determined for the temperature range from 600 ° to 900 ° C. The results of the investigation show that each source of carbon reacts significantly with the Cr2 03 and that the reactivity of each form of carbon depends on the reaction temperature , and each form is independent of the other . Radioisotope and gas - analysis techniques are discussed and a description of the experimental apparatus is given .

Jan 1, 1964

By Jacob Masliyah, Zhenghe Xu, Lujie Yan

"Understanding adsorption mechanism of polymeric organic process modifierssuch as carboxymethyl cellulose (CMC) on talc hasbeen a major challenge due to anisotropic nature of talc basal planes and edge surfaces. The main objective of this study is to investigate the adsorption of CMC on the basal planes and edge surfaces of talc.Smooth basal plane and edge surfaces of talc were prepared successfully by simple cleavage and sophisticated ultramicrotome cutting method, respectively. The prepared surfaces were characterized by atomic force microscope (AFM) imaging to be sufficiently smooth for colloidal probe force measurements using AFM. Anisotropic surface charge characteristics were determined,with the basal planes to carry a permanent negative surface charge and edge surfaces featuring a pH-dependent charge characteristic. The adsorption of CMC on talc basal plane and edge surfaces at pH 9 in KClaqueous solutions of various ionic strengths wasinvestigated by in situ AFM imaging technique. Themorphology of adsorbed CMC on talc basal planes and edge surfaces was found to be significantly different, due to different binding mechanisms involved. Interaction of CMC with the talc basal plane was found to bedominated by hydrophobic interactions while its binding with the talc edge surface was mainly through chemical complexation and hydrogen bond. The amount of CMC adsorbed on both talc basal planes and edge surfaces increased with increasing ionic strengthof solutions. The methodology developed in our study opens the door to probe polymer adsorption on anisotropic phyllosilicate surfaces, which can help us better understand the mechanism of polymer adsorption on specific mineral faces."

Jan 1, 2014

By Sameh M. Khella

This paper discusses the application of deep CFA piles for the foundation of structures in different ground stratifications with a focus on the application in Queensland region. Design, construction techniques and quality measures implemented during these procedures are described. Testing methods and verification of capacity, integrity and performance of these piles are also demonstrated. Case studies for this application are presented with an appreciation of this solution within the provided project conditions of each case. Examples of successes and challenges encountered over the course of application of deep CFA in Queensland are mentioned. Limitations of the technique and less favourable situations for its implementation are also highlighted.

Nov 1, 2022

By G. Purcell

When coal in an oil/water slurry is ground to minus-200-mesh in a ball mill, some of the mill energy, normally wasted as heat, can be usefully recovered to help emulsify the oil. If the discharge flows onto a suitable sized trommel screen, water and ash material are rejected through the screen while coal and oil ball together to give a clean coal product. A small (6-lb/hr) continuous plant has demonstrated the feasibility and the limitations of this process for New Mexico coals.

Jan 1, 1980